CHARACTERIZACIóN MORFOHISTOLóGICA DE FRUTOS EN ESPECIES ARGENTINAS DE LEPECHINIA (LAMIACEAE - NEPETOIDEAE - MENTHEAE).

As part of an integral study of fruits belonging to native argentinean species of Lamiaceae, we conducted a research of Lepechinia Willd. native species (Lamiaceae-Nepetoideae-Mentheae). The aim of the present investigation was to perform a detailed morphohistological fruit characterization of L. floribunda, L. meyenii and L. vesiculosa and evaluate the possible taxonomic value of these characters. We worked with fresh and herbarium material. The observations were made with light microscopy and scanning electron microscopy. Shape, color and presence of the abscission scar waxes were the exomorphological diagnostic characters while abscission scar shape and position, and the surface SEM view of nutlets did not show differences for all three species. In terms of histology, L. floribunda and L. meyenii have similar pericarp structure, differing only by the thickness of the layers. In contrast, L. vesiculosa shows differences at the mesocarp. [ABSTRACT FROM AUTHOR]